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61.
62.
Daniel Plusquellec Catherine Brenner-Hénaff Pascale Léon-Ruaud Stéphane Duquenoy Martine Lefeuvre Henri Wróblewski 《Journal of carbohydrate chemistry》2013,32(5):737-751
Abstract Treatment of free glycosylamines with 3-acyl-5-methyl-1,3,4-thiadiazole-2 (3H)-thiones 6 or with acids and 5-methyl-2-thioxo-1,3,4-thiadiazole-3(2H)-carbothioic acid S-(5-methyl-1,3,4-thiadiazol-2-yl) ester 7 in hydroorganic media afforded N-acylglycosylamines in high yields and without any competitive deglycosylation. This reaction found applications in the synthesis of N-glycopeptide building blocks and of glycosidic non ionic surfactants. Results concerning surface activities of two N-acylglycosylamines are reported. The new non ionic N-octanoyl-β-D-glucosylamine surfactant exhibited efficacy and selectivity in the extraction of membrane proteins, enhanced the activity of a membrane succinate dehydrogenase and proved thus useful for membrane studies. 相似文献
63.
Magnin G. Sergent M. Coen S. Périchaud A. Phan-Tan-Luu R. 《Journal of Thermal Analysis and Calorimetry》2000,61(1):51-61
Thermal degradation of polystyrene and polyvinylchloride was studied by thermomanometric analysis. A design of experiments
was used to quantify the influence of 8 physico-chemical parameters on the responses of the analyser and on the different
types of degradation compounds.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
64.
John D. Harvey Stuart G. Murdoch Stephane Coen Rainer Leonhardt David Mechin Gordon K. L. Wong 《Optical and Quantum Electronics》2007,39(12-13):1103-1114
Optical parametric amplification is an important nonlinear process in photonic crystal fibres driven by the small effective area and the special dispersion characteristics of these fibres. Aside from its role in supercontinuum generation, parametric amplification can lead to efficient wavelength conversion, limited primarily by the uniformity of the diameter of currently available fibres. The related Bragg scattering process can be used for both wavelength conversion and optical switching, again limited by the physical characteristics of the fibres used. 相似文献
65.
66.
Nonlinear Galerkin methods and mixed finite elements:
two-grid algorithms for the Navier-Stokes equations 总被引:14,自引:0,他引:14
Summary.
A nonlinear Galerkin method using mixed finite
elements is presented for the two-dimensional
incompressible Navier-Stokes equations. The
scheme is based on two finite element spaces
and for the approximation of the velocity,
defined respectively on one coarse grid with grid
size and one fine grid with grid size and
one finite element space for the approximation
of the pressure. Nonlinearity and time
dependence are both treated on the coarse space.
We prove that the difference between the new
nonlinear Galerkin method and the standard
Galerkin solution is of the order of $H^2$, both in
velocity ( and pressure norm).
We also discuss a penalized version of our algorithm
which enjoys similar properties.
Received October 5, 1993 / Revised version received November
29, 1993 相似文献
67.
In this work, a two-phase film-flow model in a hygroscopic capillary tube is developed and extended to describe the two-phase capillary viscous transport in a network of parallel capillary tubes in terms of relative permeabilities. This film-flow approach is further considered to predict the longitudinal moisture transport in oak wood during drying. Numerical results obtained from this prediction are compared with data of convective drying experiments performed on samples of this wood. The comparison seems to confirm the physical relevance of a film-flow model to correctly represent the moisture transfer until the hygroscopic regime is reached. 相似文献
68.
Approximate inertial manifolds for reaction-diffusion equations in high space dimension 总被引:4,自引:0,他引:4
Martine Marion 《Journal of Dynamics and Differential Equations》1989,1(3):245-267
The concept of approximate inertial manifolds was introduced by Foiaset al. (1987) in the case of the two-dimensional Navier-Stokes equations. These manifolds are finite dimensional smooth manifolds such that the orbits enter a very thin neighborhood of the manifold after a transient time; this concept replaces the one of inertial manifold when either an inertial manifold does not exist or its existence is not known. Our aim in this paper is to prove that approximate inertial manifolds exist for reaction-diffusion equations in high space dimension by opposition with exact inertial manifolds whose existence has only been proved in low dimension and for which nonexistence results have been obtained in space dimensionn=4. 相似文献
69.
On the occasion of the celebration of Prof. Rosa Caballol's 65's birthday, a symposium was organized by the Quantum Chemistry Group of the Universitat Rovira i Virgili (Tarragona, Spain) under the title “Theoretical Chemistry in Spain told by women.” The symposium gave a representative illustration of the research in theoretical chemistry in Spain, which is not only very diverse, but also in many areas at the forefront of the field. In this article, we summarize the contributions made by Rosa Caballol and coworkers. Emphasis lies on the developments of wave function based methods to accurately describe electron correlation effects in systems with unpaired electrons. Besides discussing some illustrative applications, we will also explore the limits of the existing methods and outline the perspectives of how one can possibly overcome them. © 2014 Wiley Periodicals, Inc. 相似文献
70.
We examine in this paper some properties of Morita and Prüfer hulls of FCP and FIP extensions of rings. Dichotomy phenomena appear in the case of a quasi-local base ring. In the general case, we define relative supports that allow us to introduce the concept of direct factorization of an extension and to characterize these hulls. 相似文献